JP2002237300A - Battery containing pellet constituting double current- collector screen cathode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide electrode structure having the form of a first active material/a current collector/a second active material. SOLUTION: One of electrode active materials cannot be moved to the opposite side through the current collector when it is in a coagulated state, but in the non-coagulated state, the electrode active material can be communicated through the current collector. On the other hand, the second active material is powder that cannot be communicated through the current collector in the coagulated state nor in the non-coagulated state. To finish electrode structure, the aggregate of the first active material/the current collector/the second active material is pressed in the direction of the second electrode active material from the first electrode active material, or in the reverse direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to the conversion of chemical energy into electrical energy. More specifically, the present invention relates to a novel sandwich-like cathode design and a process for manufacturing the same. Sandwich electrodes are used as the cathode of primary lithium batteries and the positive electrode of secondary lithium-ion batteries. These designs are particularly useful in powering such batteries for implantable medical devices.

[0002]

BACKGROUND OF THE INVENTION Early medical devices often used at least two lithium electrochemical cells in series as their power source. However, these electrical circuits now consume less energy than before. This has recently made it possible to use a single lithium battery as a reliable power source. In the case of a single battery design, the need for high power density in many applications is greater than lower power density due to lower pulse voltage. Therefore, a large electrode surface area is required to achieve this requirement. However, the greater the electrode surface area, the greater the amount of inert material (current collectors, separators, etc.) introduced into the system, resulting in a reduction in the volume capacity of the battery. In addition, attention must be paid to the life of the medical device, which depends on battery capacity and power efficiency.

[0003] high rate cathode material mixed with an attempt to use such as SVO high volume of material, such as CF _x is
U.S. Patent No. 5,18 to Weiss et al.
0,642. However, electrochemical cells made with this type of cathode mixture have relatively low capacity. As part of the cathode mixture, CF _x
The advantage of increasing the theoretical capacity of the battery by using a PDP is partly by lowering its electrical potential in high rate discharge applications required in implantable cardiac defibrillators. Is to be balanced.

[0004] An important solution to this problem is U.S. patent application Ser. No. 09 / 09,978 to Gunn et al., Assigned to the assignee of the present invention and entitled "Sandwich Cathode Design for Alkali Metal Electrochemical Cells with High Rate Capacity." / 560,060, which is hereby incorporated by reference. This application covers silver vanadium oxide (SVO) and fluorocarbon (C
A novel sandwich-like electrode design using F _x ) is disclosed. Typical sandwich electrode has the following form: SVO / current collector screen / CF _x / current collector screen / SVO.

However, if the opening of the current collector screen is too large, one of the active materials may communicate with the other side of the current collector during the manufacturing process. This "contamination" is undesirable because it impairs the discharge characteristics. In particular, S
VO is present with possible output of a high rate, a lower energy density than CF _x. Thus, contamination by other active materials at the interface between the current collector and one of the active materials destroys the primary purpose of each active material located on either side of the current collector and separated from each other. It is not desirable.

[0006]

In order to maintain the improved dischargeable output of a battery containing a sandwich electrode, it is necessary to maintain direct contact of both the first and second electrode materials on both sides of the current collector. is there. Good contact or adhesion leads to good conductivity at the good interface during discharge. Although obvious in theory, in practice the conductivity on this boundary is greatly influenced by the manufacturing method or process. When the current collector is a screen, one of certain electrode materials may pass through the opening of the current collector and be trapped between the other electrode material and the current collector. This will reduce the interface conductivity between the current collector and the "contaminated" first electrode material.

[0007]

SUMMARY OF THE INVENTION Accordingly, the method of the present invention includes the step of bringing one of the electrode active materials into an agglomerated state in which it cannot move through the current collector to the opposite side. However, in the non-aggregated form, one electrode active material can communicate through the current collector. The other material, the second active material, is in a state where communication through the current collector is impossible, whether or not it is in a powdered state. Therefore, the first active material /
The current collector / second active material aggregate is pressed in the direction from the first active material to the second active material or vice versa.

In this regard, the present invention provides an anode,
The invention is directed to an electrochemical cell comprising a cathode, wherein at least one of the anode and cathode is essentially a first
Positioning the electrode active material in the compression fixing member;
Positioning the current collector screen on the top of the first electrode active material, positioning the second electrode active material on the top of the first current collector screen, and positioning the second current collector screen on the second current collector screen;
Locating the top of the electrode active material, locating the third electrode active material on the top of the second current collector screen, thereby forming an electrode assembly, and compressing the electrode assembly. And a step of forming an electrode, further comprising a separator for electrically insulating the anode from the cathode, and an electrolytic solution acting on the anode and the cathode.
When the electrode active material is in a non-aggregated state, both have a non-aggregated size smaller than the opening size of at least one opening of the current collector screen, and are movable through at least one opening. Further, when the first and third electrode active materials are in an aggregated state, these materials cannot pass through at least one opening in the current collector screen, and further, the second electrode active material always collects. The electrode assembly cannot pass through at least one opening of the electric body, and further, the electrode assembly is moved from the first electrode active material to the third electrode active material.
Alternatively, the pressure is applied in any direction from the third electrode active material toward the first electrode active material.

[0009] These and other objects of the present invention will become more apparent to those skilled in the art (the skilled artisan) by reference to the following description.

The electrochemical cell according to the invention is either a primary chemistry or a secondary rechargeable chemistry.
For both primary and secondary types, the battery is an anodic activating metal selected from Groups IA, IIA and IIIB of the Periodic Table of the Elements, including lithium, sodium, potassium, and the like, and alloys thereof. Intermetallic compounds, including, for example, intermetallic compounds and intermetallic compounds including Li-Si, Li-Al, Li-B, Li-Mg and Li-Si-B alloys are included. The preferred metal comprises lithium. Another negative electrode comprises a lithium alloy, such as a lithium-aluminum alloy. However, the higher the amount of aluminum by weight in the alloy, the lower the energy density of the battery.

In a primary battery, the anode consists of a thin metal sheet, or foil of anode metal, and is pressed or rolled onto a metal anode current collector, ie, preferably a current collector made of nickel, Form a negative electrode. In a typical battery of the present invention, the negative electrode has the same material as the current collector, that is, has a long tab or lead wire preferably made of nickel, and has a negative electrode type conductive metal battery case. It is formed integrally, such as by welding, or is contacted thereto by welding. In another method, the negative electrode is formed in some other geometry, such as a bobbin, cylinder or pellet, to allow for a battery design that forms an alternating low surface.

In a secondary electrochemical system, the anode, the negative electrode, is capable of intercalating (insertion reaction) and deintercalating (extraction reaction) an anode active material, preferably lithium alkali metal. Composed of various anode materials. Various forms of carbon that can reversibly retain lithium species (eg, coke, graphite,
A carbonaceous negative electrode material comprising acetylene black, carbon black, vitreous carbon, etc.) is preferred as the anode material. "Hairy carbon" (hairy carbon)
The material is particularly preferred because of its relatively high lithium retention capacity. "Hairy carbon" is disclosed in U.S. Pat.
No. 43,928, which is hereby incorporated by reference. Graphite is another preferred material. Regardless of the form of carbon, carbon-based material fibers are particularly advantageous. This is because they have excellent mechanical properties that can be produced in a robust electrode that can withstand degradation during repeated charge / discharge cycles. In addition, the large surface area of the carbon fibers allows for rapid charge / discharge rates.

A typical negative electrode for a secondary battery is about 9
0 to 97% by weight of "hairy carbon" or graphite (graphite) and about 3 to 10% by weight of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDE), polyethylene tetrafluoroethylene (ETFE), polyamide, polyimide And a fluororesin powder such as a mixture thereof. The negative electrode mixture is provided on a current collector, such as nickel, stainless steel or copper foil, or a screen, by casting, compression, rolling, or otherwise contacting the mixture thereto.

In either case of a primary battery or a secondary battery, the action at the positive electrode involves the process of converting ions transferred from the negative electrode to the positive electrode into an atomic or molecular form. For a primary battery, the cathode active material comprises a carbon-based chemical or at least a first transition metal chalcogen constituent, which may be a metal, a metal oxide or a mixed metal oxide comprising the first and second metals or their oxides, And possibly a third metal or metal oxide or a mixture of first and second metals or a mixture of host metal oxides, the metal oxide of which is integrated. The cathode active material can also include a metal sulfide.

The carbon-based active material is preferably coke,
It can be prepared from carbon and fluorine, including graphitic and non-graphitic forms of carbon such as charcoal or activated carbon. Fluorocarbon is represented by the formula (CF _x ) _n , where x is about 0.1
And 1.9, preferably between about 0.5 and 1.2, and in (C ₂ F) _n , n represents the number of widely varying monomer units.

One preferred mixed metal oxide is a transition metal oxide having the general formula SM _x V ₂ O _y , wherein SM is IB to VIIB and VI of the Periodic Table of the Elements.
II, and in the general formula x
Is about 0.30 to 2.0 and y is about 4.5 to 6.0. For illustrative purposes, and not intended to be limiting, one representative cathode active material is a vanadium oxide having the general formula, Ag _x V ₂ O _y , in one of its many phases. Silver, that is, the general formula x = 0.3
Β phase with 5 and y = 5.18 and the general formula x = 0.80
And a gamma phase having y = 5.40 and a general formula x = 1.0 and y
= 5.5, a combination of these phases and silver vanadium oxide mixed with them. A more detailed description of such cathode active materials is given in U.S. Pat. No. 4,311, by Liang et al., Assigned to the assignee of the present invention.
No. 0,609, incorporated herein by reference.

Another preferred mixed transition metal oxide cathode material includes V ₂ Oz. Where z ≦ 5,
This material comprises Ag ₂ O with silver in the oxidation state of silver (II), silver (I) or silver (O), and copper of either copper (II), copper (I) or copper (O). coupled with the CuO, general formula, there is provided a mixed metal oxide having a _{Cu x Ag y V 2 O 2} (CSVO). Therefore, synthetic (composite) cathode active material is a metal oxide - metal oxides - metal oxide, metal - metal oxide - metal oxides, or metal - metal - can be described as a metal oxide, also Cu _x Ag _y
The range of material components found in V ₂ O _z is preferably about 0.01 ≦ z ≦ 6.5. A common form of CSVO is Cu _0.16 Ag _0.67 V ₂ O ₂ , where z is about 5.5,
In addition, z is about 5.75 in Cu _0.5 Ag _0.5 V ₂ O ₂ . The oxygen content is represented by z, which is the exact stoichiometric ratio of oxygen in the CSVO, when the cathodic material is prepared in an oxidizing atmosphere such as air or oxygen, or in the presence of argon, nitrogen and helium. This is because it largely depends on whether or not it is prepared in such an inert atmosphere. For a more detailed description of this cathode active material, reference is made to Takeuchi et al., US Pat. No. 5,472,810 and Takeuchi et al., US Pat. No. 5,516,340. Both patents are assigned to the assignee of the present invention and are incorporated herein by reference.

In addition to the above-mentioned fluorocarbon, silver vanadium oxide, copper / silver vanadium oxide, Ag ₂ O, Ag ₂
O ₂ , CuF ₂ , Ag ₂ CrO ₄ , MnO ₂ , V ₂ O
₅ , MnO ₂ , TiS ₂ , Cu ₂ S, FeS, FeS
_2. Copper oxide, copper vanadium oxide, and mixtures thereof are considered as effective active materials.

In a secondary battery, the positive electrode is stable in air
From lithium oxide materials that are easy to process.
Preferably. This kind of air-stable lithiated catho
Examples of active materials include vanadium, titanium, chromium, copper,
Molybdenum, niobium, iron, nickel, cobalt and magnesium
Metal oxides, sulfides, selenides (selen
), And tellurides
Is included. More preferred oxides include LiNiO_Two , L
iMn_Two O_Four , LiCoO_Two , LiCo_0.92Sn _0.08O
_Two And LiCo_1-x Ni_x O_Two Is included.

To charge such a secondary battery, lithium ions comprising a positive electrode are intercalated into a carbonaceous negative electrode by applying an externally generated potential to the battery. The resulting Li _x C ₆ negative electrode has an x range between 0.1 and 1.0. This creates a potential in the battery which is discharged in the usual way.

The above-described cathode active material, whether in primary or secondary chemical form, comprises a sandwich electrode body for incorporation into an electrochemical cell by mixing one or more of these with a binder material. Formed. A suitable binder material is a powdered fluoropolymer, more preferably from about 1 to about 5 parts of the cathode mixture.
Powdered polytetrafluoroethylene or powdered polyvinylidene fluoride present in weight percent. Further, up to about 10% by weight of a conductive diluent is preferably added to the cathode mixture to improve conductivity. Suitable materials for this purpose include acetylene black, carbon black and / or graphite, or metal powders such as powdered nickel, aluminum, titanium and stainless steel. Thus, a preferred cathode activating mixture includes about 1-5% by weight of a powdered fluoropolymer binder, a conductive diluent present at about 1-5% by weight, and about 90-98% by weight of the cathode active. Substance included.

According to the present invention, two different materials of the above-described cathode active materials, whether in primary or secondary chemical form, come into contact with opposing sides of the current collector. Preferably, the first active material on the current collector facing the anode has a lower energy density, but a greater rate of possible output than the second active material on the opposite side of the current collector, and Is separated from In other words, the representative second cathode active material does not directly face the lithium anode.

A preferred first cathode active material having a high rate of possible power but a lower energy density is a mixed metal oxide such as SVO or CSVO. This material is typically provided by about 94% by weight SVO and / or CSVO and 3% by weight binder, and 3% by weight conductive diluent as the element facing the anode. The second active material in contact with the opposite side of the current collector is, for example, CF _x. This material is preferably provided as a second active material having about 91% by weight CF _x , 5% by weight binder and 4% by weight conductive diluent.

Suitable current collectors are stainless steel,
It is selected from the group consisting of titanium, tantalum, platinum, gold, aluminum, cobalt nickel alloys, high alloy ferritic stainless steels containing molybdenum and chromium, and nickel-, chromium- and molybdenum-containing alloys. The preferred current collector material is titanium, most preferably having a thin layer of graphite / carbon material, iridium, iridium oxide or platinum applied thereto on a titanium cathode current collector. The cathode prepared as described above was wound in a form operatively associated with at least one or more plates of anodic material or with a strip anodic material having a structure resembling a "jelly roll". It can be a corresponding strip.

Therefore, one typical cathode assembly is a current collector of the following form: SVO / current collector screen / C
It has active material elements connected in parallel with each other via F _x / current collector screen / SVO and short-circuited.

Another exemplary cathode assembly has the following form: SVO / current collector screen / CF _x , where the anode is lithium and the SVO faces the anode.

When the opening in the current collector screen is of a size larger than one particle size of the active material, some of the active material can move through the opening and the other on the opposite side of the current collector. Contaminates the contact interface with the active material.
The particular nature of the contaminants, although having a higher energy density, is not always the only thing that matters in terms of a lower rate of possible output or not. It should be noted that any contamination of the active material / collector interface (interface) by other active materials is undesirable.

According to one embodiment of the present invention, one of the first and second active materials is in a non-agglomerated state and has a size smaller than at least one opening of the current collector screen. If present, this material can pass through the opening. Such an example is found in powdered non-aggregating active materials. Thus, according to the present invention, the active material disables communication through the current collector by bringing the material into an agglomerated state. The agglomerated state is defined as a state in which the active particles are firmly held together as a part of the same aggregate and are firmly attached to each other, and are a group of particles in the main body that connects the entire aggregate. Examples of agglomerated states include providing one active material in compressed pellet or sheet form.

Methods for providing the active material in sheet form are described in US Pat. Nos. 5,435,874 and 5,5,874.
No. 71,640, both of which are by Takeuchi et al., Which are also assigned to the assignee of the present invention, and are hereby incorporated by reference. These patents teach starting with an underlying card active material mixed with a conductive diluent and a suitable binder material and suspending the starting mixture in a solvent to form a paste. The mixed paste is supplied to a roller and formed into briquettes (briquettes or trapezoids) or pellets, and then supplied to a rolling mill to form a sheet-like cathode active material. The sheet is finally dried and stamped into a plate of the desired shape.

[0030] The pellets can be prepared by any method known to those skilled in the art.
About 0.1 ton / cm of the active mixture ^Two About 4 tons /
cm^Two Provided by pressing under pressure.
Typical activity that can be easily pressed into pellet form
As the substance and its composition, 91% by weight of SVO, 3
Wt% PTFE, 2 wt% KETJENBLACK
And 1% by weight of graphite, 91% by weight
% CF_x 4% by weight PTFE and 5% by weight
Wenigan Acetylene Black (Shawenig)
an Acetylene Black)
98% by weight of CF_x 1% by weight PTFE, and
From 1% by weight of Shawenigan acetylene black
What, 100% by weight of SVO, 100% by weight of Ag
_Two O, and 100% by weight of AgO.

The other active material may be a particle that cannot move through at least one opening in the current collector screen, even when it is in a non-agglomerated state. In this regard, the active material may be provided in the form of pellets or sheets or a powder with a particle size that is too large to move through the openings in the current collector.

According to the present invention, the sandwich electrode forms an aggregate formed by applying two types of active materials on both sides of the intermediate current collector in the direction from the first cathode active material to the second active material. Alternatively, it is formed by pressing (pressing) in the opposite direction. If one active material is in a non-aggregated state, it communicates through the current collector, but it is actually in an aggregated state, and the other active material cannot pass through the current collector, whether or not in an aggregated state In the end, the possibility of any contamination of the current collector / active material interface is eliminated.

The electrode structure of the present invention includes the following: first, a first electrode active material / current collector screen / second electrode active material / current collector screen / first electrode active material, wherein The first and second electrode active materials are different. Alternatively, the first electrode active material / current collector screen / second electrode active material / second electrode active material / current collector screen / first electrode active material, wherein the first and second electrode active materials are different. Things.

Another embodiment of the present invention has the following form:
First electrode active material / Current collector screen / First electrode active material /
Second electrode active material / First electrode active material / Current collector screen /
It comprises a first electrode active material, wherein the first and second electrode active materials are different.

In order to prevent internal short circuit conditions, the sandwich cathode is provided with a suitable separator material IA,
Separated from Group IIA or IIIB anodes. The separator is an electrically insulating material, is chemically non-reactive with the anode and cathode active materials, and is chemically non-reactive and insoluble in the electrolytic solution. In addition, the separator material has a sufficient degree of porosity to allow flow through the electrolyte during the electrochemical reaction of the battery. Illustrative separator materials can include fabrics woven from fluoropolymer fibers. The fibers include polyvinylidene fluoride, polyethylene tetrafluoroethylene, polyethylene chlorotrifluoroethylene, either alone or in fluoropolymer microporous.
Film, non-woven glass, polypropylene, polyethylene, glass fiber material, ceramics, name ZI
Polytetrafluoroethylene membrane commercially available under TEX (Chemplast Inc.), polypropylene membrane commercially available under the name CELGARD (Celanese Plastics Company, Inc.), and DEXIGLAS (CH.
Dexter, Div. ,) There is a commercially available membrane under Dexta Corporation).

The electrochemical cell of the present invention further includes a non-aqueous, ionically conductive electrolyte that acts as a medium for the transfer of ions between the anode and cathode electrodes during the electrochemical reaction of the cell. Electrochemical reactions at the electrodes involve the conversion of ions transferred from the anode to the cathode into atomic or molecular forms. Thus, a water-insoluble electrolyte suitable for the present invention is substantially inert to the anodic and cathodic materials and possesses the physical properties required for ion transfer, namely low viscosity, low surface tension and wettability. Present.

A suitable electrolyte has an inorganic ionic conductive salt that is soluble in a water-insoluble solvent. More preferably, the electrolyte contains an ionized alkali metal salt that melts in a mixture of an aprotic organic solvent consisting of a low viscosity solvent and a high (absolute) dielectric constant solvent. The inorganic ion conductive salt acts as a mediator for anode ion transfer and intercalates with the cathode active material. Preferably, the ion forming alkali metal salt is similar to the alkali metal forming the anode.

In the case of a lithium anode, the alkali metal salt of the electrolyte is a lithium-based salt. Known lithium salts that are advantageous as vehicles for transporting alkali metal ions from the anode to the cathode include LiPF ₆ , LiBF ₄ , L
iAsF ₆ , LiSbF ₆ , LiClO ₄ , LiO ₂ ,
LiAlCl ₄ , LiGaCl ₄ , LiC (SO ₂ CF
₃ ) ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiSCN, Li
O ₃ SCF ₃ , LiC ₆ F ₅ SO ₃ , LiO ₂ CCF
₃ , LiSO ₆ F, LiB (C ₆ H ₅ ) ₄ , LiCF ₃
Contains SO ₃ and mixtures thereof.

The low-viscosity solvents which are advantageous in the present invention are tetrahydrofuran (THF), methyl acetate (MA), diglyme, tridylm, tetraglyme, dimethyl carbonate (DMC), 1,2-dimethoxyethane (DME),
1,2-diethoxyethane (DEE), 1-ethoxy,
Esters, such as 2-methoxyethane (EME), ethyl methyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, diethyl carbonate, dipropyl carbonate, and mixtures thereof, linear esters and cyclic ethers and Dialkyl carbonates and cyclic carbonates, cyclic esters and cyclic amides such as propylene carbonate (P
C), ethylene carbonate (EC), butylene carbonate, acetonitrile, dimethyl sulfoxide, dimethyl formamide, dimethyl acetamide, γ-valerolacto, γ-butyrolactone (GBL), N-methyl-pyrrolidine (NMP), and A high absolute dielectric constant solvent such as a mixture thereof. In the present invention, a preferred anode is lithium metal, and a preferred electrolyte is a 50:50 volume ratio of a mixture of propylene carbonate as a preferred high absolute dielectric constant solvent and 1,2-dimethoxyethane as a preferred low viscosity solvent. 0.8M melted into
It is LiAsF ₅ or LiPF ₆ in 1.5M from.

A preferred electrolyte for a secondary battery according to the present invention comprises a solvent mixture of EC: DMC: EMC: DEC. The most preferred volume percent ranges for the various carbonate solvents are EC in the range of about 20% to about 50%, DMC in the range of about 12% to about 75%, and about 5% to about 4%.
EMC in the range of 5% and D in the range of about 3% to about 45%.
Including EC. In a preferred form of the invention, the electrolyte interacting with the cell is equivalent with respect to the DMC: EMC: DEC ratio. This is important for maintaining consistent and reliable cycling characteristics. Due to the presence of low potential (anode) material in the charged cell, an unbalanced mixture of DMC: DEC (LiC ₆ -0.01 V vs. Li / Li ⁺ ) in the presence of lithiated graphite causes significant amounts of EMC. Are known to result. D
When the concentrations of MC, DEC and EMC change, the cycle characteristics and the cell temperature rating change. Such unpredictability is unacceptable. This phenomenon is illustrated in US patent application Ser. No. 09/6, filed Sep. 26, 2000, assigned to the assignee of the present invention.
No. 69,936, which is hereby incorporated by reference. Electrolytes containing the quaternary carbonate mixtures of the present invention exhibit a freezing point below -50 ° C, and lithium ion secondary cells activated by such mixtures have very low temperatures below -40 ° C. In addition to showing excellent discharge characteristics and charge / discharge cycle characteristics, it also shows very excellent cycle characteristics at room temperature.

The assembly of cells described here is preferably in the form of a winding element structure. That is, the manufactured negative electrode, positive electrode and separator are wound together in a jelly roll type shape, or the negative electrode is outside the roll, and the cell / case is electrically connected to the case negative potential type. To form a wound element cell laminate. Using suitable top and bottom insulation, the wound cell stack is inserted into a suitably sized metal case. The metal case may be made of materials such as, but not limited to, stainless steel, mild steel, nickel-plated mild steel, titanium, tantalum or aluminum, as long as the metallic material does not interfere with the cell elements. Become.

The cell header is comprised of a metal disk-shaped body and has a first hole for receiving a glass-to-metal seal / terminal pin feedthrough and a second hole for filling with electrolyte. The glass used is CABAL 12, TA 23, FUSITE 4
Corrosion-resistant type containing up to about 50% by weight of silicon, such as 25 or FUSITE 435. The positive terminal pin feedthrough is preferably made of titanium, but molybdenum, nickel alloy, or stainless steel can also be used. The cell header is generally the same as the material of the case. The positive terminal pins supported within the glass-to-metal seal are then supported on a header welded to the case containing the electrode layers. Thereafter, the cell is filled with the above-described electrolyte solution, and the filling hole is hermetically sealed by, for example, close welding with a stainless steel ball over the filling hole.

The above assembly describes a case negative potential cell which is a preferred structure of a typical secondary cell of the present invention. As is well known to those skilled in the art, a typical secondary electrochemical system of the present invention can be configured in a case positive potential configuration.

It will be understood that various modifications to the inventive concept described herein will be apparent to those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims. Would.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01M 4/48 H01M 4/48 4/50 4/50 4/54 4/54 4/58 4/58 4 / 66 4/66 A 6/16 6/16 A 10/40 10/40 AZ (72) Inventor Sally Anne Smesco United States of America, 14120, New York, North Tonawanda, Hewitt Street 396 (72) Inventor Esther S. Takeuchi 14051, New York, United States, East Amherst, Saint-Raphael, Court 38 F-term (reference) 5H017 AA03 AS01 BB08 CC01 DD05 EE01 5H024 AA00 BB05 BB08 DD14 EE01 EE05 FF14 FF18 FF19 FF31 5H029 AJ02 AL07 AL08 AL AL12 AL13 AM03 AM04 AM05 AM07 BJ12 CJ03 CJ22 CJ24 DJ07 DJ16 EJ01 EJ04 5H050 AA02 AA08 BA06 BA16 CA01 CA02 CA0 5 CA07 CA08 CA09 CA11 CB07 CB08 CB09 CB12 DA02 DA04 FA02 FA17 GA03 GA22 GA24 HA02

Claims (26)

[Claims] 1. a) an anode; b) a cathode, wherein at least one of the cathode and the anode is essentially: i) positioning a first electrode active material in a compression-fixed member; ii. ) Positioning the current collector screen on the top of the first electrode active material; and iii) positioning a second electrode active material different from the first electrode active material on the top of the current collector screen, thereby forming an electrode assembly. Forming the body; iv) compressing the electrode assembly to form an electrode; said cathode when formed by a method comprising: c) a separator electrically insulating the anode from the cathode; d) an electrochemical cell comprising an electrolyte acting on the anode and the cathode. 2. The first electrode active material has a size smaller than the size of at least one opening of the current collector screen in a non-aggregated state, so that the first electrode active material is movable through at least one opening. Furthermore, the second electrode active material cannot move through the at least one opening of the current collector screen while it cannot move through the at least one opening in the current collector screen in the aggregated state. And the electrode assembly is pressed against the second electrode active material in the direction of the first electrode active material or on the first electrode active material in the direction of the second electrode active material. The electrochemical cell according to claim 1, wherein: 3. The electrochemical cell according to claim 1, wherein the second electrode active material has a form selected from the group consisting of a powder, a pellet, and a sheet. 4. The method according to claim 1, wherein the first and second electrode active materials are CF._x , A
g_Two O_Two , CuF, Ag _Two CrO_Four , MnO_Two , SV
O, CSVO, V_Two O_Five , LiCoO_Two , LiNiO
_Two , LiMn_Two O_Four , CuO_Two , TiS_Two , Cu_Two S,
FeS, FeS_Two , Copper oxide, copper vanadium oxide and
2. The method according to claim 1, wherein said mixture is selected from the group consisting of mixtures thereof.
An electrochemical battery according to claim 1. 5. The method of claim 1, wherein the anode comprises lithium.
An electrochemical battery according to claim 1. 6. An electrolyte comprising tetrahydrofuran (TH)
F), methyl acetate (MA), diglyme, triglyme, tetraglyme, dimethyl carbonate (DM
C), 1,2-dimethoxyethane (DME), 1,2-
Dimethoxylene (DEE), 1-ethoxy, 2-methoxyethane (EME), ethyl methyl carbonate,
Methyl propyl carbonate, ethyl propyl
Carbonate, diethyl carbonate, dipropyl
A first solvent selected from the group consisting of carbonates and mixtures thereof, and propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate, acetonitrile, dimethyl sulfoxide, dimethyl, formamide, dimethylacetamide , Γ-valerolactone, γ-butyrolactone (G
The electrochemical cell according to claim 1, wherein the electrochemical cell is a water-insoluble chemical agent comprising a second solvent selected from the group consisting of BL), N-methyl-prololidinone (NMP), and a mixture thereof. 7. The electrolyte according to claim 1, wherein the electrolyte is a water-insoluble chemical agent,
_{PF 6, LiBF 4, LiAsF 6} , LiSbF 6, L
iClO ₄ , LiO ₂ , LiAlCl ₄ , LiGaCl
₄ , LiC (SO ₂ CF ₃ ) ₃ , LiN (SO ₂ CF
₃ ) ₂ , LiSCN, LiO ₃ SCF ₃ , LiC ₆ F ₅
SO ₃ , LiO ₂ CCF ₃ , LiSO ₆ F, LiB (C
_{6 H 5) 4, LiCF 3} SO 3 and electrochemical cell according to claim 1, characterized in that it comprises a lithium salt selected from the group consisting of mixtures. 8. The current collector screen is made of stainless steel, titanium, tantalum, platinum, gold, aluminum, cobalt nickel alloy, highly alloyed ferromagnetic stainless steel including molybdenum and chromium, and nickel, The electrochemical cell according to claim 1, wherein the electrochemical cell is selected from the group consisting of chromium- and molybdenum-containing alloys. 9. The current collector is a graphite / carbon material, iridium,
9. The electrochemical cell of claim 8, comprising titanium having a coating selected from the group consisting of iridium oxide and platinum applied thereon. 10. The electrochemical cell according to claim 8, wherein at least one electrode is a cathode having a form of SVO / current collector screen / CF _x . 11. The method according to claim 11, wherein the anode is lithium,
11. The electrochemical cell according to claim 10, wherein O faces the anode. 12. a) an anode; b) a cathode, wherein at least one of the cathode and the anode is essentially: i) fixing the first electrode active material in a compression fixing member; ii) locating the first current collector screen on the top of the first electrode active material; iii) locating the second electrode active material on the top of the first current collector screen; Positioning the current collector screen on the top of the second electrode active material; and v) positioning the third electrode active material on the top of the second current collector screen, thereby forming an electrode assembly. vi) said cathode when formed by a method comprising compressing an electrode assembly to form an electrode; c) a separator for electrically insulating the anode from the cathode; d) an anode; And an electrolyte acting on the cathode. 13. The electrochemical cell according to claim 12, wherein the first and third electrode active materials are the same, and these materials are different from the second electrode active material. 14. The electrochemical cell according to claim 12, wherein at least one electrode is a cathode having a form of SVO / current collector screen / CF _x / current collector screen / SVO. 15. The non-aggregated state of the first and third electrode active materials, both of which have a non-agglomerated dimension smaller than an opening dimension of at least one opening of the current collector screen, so that the at least The second electrode active material is movable through one opening, but cannot move through at least one opening in the current collector screen in the aggregated state, whereas the second electrode active material is movable through at least one opening in the current collector screen. And the electrode assembly is pressed in either the direction from the first electrode active material to the third electrode active material or the direction from the third electrode active material to the first electrode active material. The electrochemical cell according to claim 12, wherein: 16. The method according to claim 16, wherein the second electrode active material is a powder, a pellet,
The electrochemical cell according to claim 12, wherein the electrochemical cell has a form selected from the group consisting of: 17. The method according to claim 17, wherein the first, second and third electrode active materials are C
F _x , Ag ₂ O ₂ , CuF, Ag ₂ CrO ₄ , MnO
_{2, SVO, CSVO, V 2} O 5, LiCoO 2, Li
NiO ₂ , LiMn ₂ O ₄ , CuO ₂ , TiS ₂ , Cu
₂ S, FeS, FeS _2, copper oxide electrochemical cell according to claim 12, characterized in that one selected from the group consisting of copper vanadium oxide, and mixtures thereof. 18. A first electrode active material; a) positioning the first electrode active material on the compression fixing member; b) positioning a first current collector screen on top of the first electrode active material; c) a first electrode active material. Positioning a second electrode active material different from that on the top of the first current collector screen, thereby forming an electrode assembly; and d) compressing the electrode assembly to form an electrode. For producing an electrode for an electrochemical cell. 19. The first electrode active material has a smaller size than at least one opening of the first current collector screen in a non-aggregated state, so that the first electrode active material can move through the at least one opening. However, in the aggregated state, it cannot move through the at least one opening in the first current collector screen, and the second electrode active material cannot move through the at least one opening in the current collector screen. In this case, the electrode assembly is pressurized either in the direction from the first electrode active material to the second electrode active material or in the direction from the second electrode active material to the first electrode active material. The method of claim 18, wherein 20. The method of claim 18, including providing a second electrode active material having a morphology selected from the group consisting of powder, pellets, and sheets. 21. The method according to claim 18, wherein the first electrode active material is not a powder in its aggregated state. 22. At least one of the electrodes, the method according to claim 18, characterized in that a cathode having a SVO / current collector screen / CF _x becomes form. 23. a) positioning a second current collector screen on top of the second electrode active material; and b) positioning a third current collector screen on top of the second current collector screen, thereby: 20. The method of claim 18, further comprising providing an electrode assembly comprising: forming an electrode assembly; and c) compressing the electrode assembly to form an electrode. 24. CF_x , Ag_Two O, Ag_Two O_Two , Cu
F, Ag_Two CrO_Four , MnO_Two , SVO, CSVO, V
_Two O_Five , LiCoO_Two , LiNiO_Two , LiMn _Two O
_Four , CuO_Two , TiS_Two , Cu_Two S, FeS, FeS
_Two , Copper oxide, copper vanadium oxide and mixtures thereof
From the group consisting of the first, second and third electrode active materials.
The method of claim 23, comprising the step of selecting. 25. The method according to claim 23, wherein the first and third electrode active materials are the same, and these materials are different from the second electrode active material. 26. The method of claim 23, wherein at least one electrode comprises providing a cathode having the form SVO / current collector screen / CF _x / current collector / SVO.